Motorola STARLINE SERIES Instructions d'exploitation télécharger pdf (Page 34)

Amplifier Setup 3-13

BLE*/* Installation and Operation Manual

It is recommended that you:

 Do not use wire jumpers to bypass the SRE-*-* location

 Perform the return optical link set up before performing amplifier set up

 Specify reverse alignment design levels for a single carrier

 Consider sweep equipment as a single carrier and operate at design levels

 Do not include injection point losses in reverse design levels

If JXP THERM devices (JXP-TH*C) are specified for level control, they should be installed in

the JXP THERM pad facility (illustrated in Figure 2-8).

Alignment Procedure

The return amplifier configuration includes one low-gain (25 dB) or one high-gain (30 dB) return

amplifier hybrid, and an appropriate SRE-*-* equalizer. All components are plug-in and are

easily installed.

To align the return path:

1 If the BLE*/* is powered, remove all fuses before you perform the following steps.

2 If necessary, carefully install a reverse hybrid amplifier.

3 Ensure that both hybrid screws are tight. Torque the screws to 10 to 12 in-lbs. Over torque

can damage the hybrid.

4 Install the design value pad in the return output pad location (JXP OUT).

5 Install the design value return equalizer, SRE-*-*, in the RTN EQ location.

6 Verify that the return input pad location (JXP-IN) has a 0 dB pad (or JXP-ZX jumper)

installed.

7 If you ordered the optional ICS, verify that the switch is installed in the ICS location. If it

was not ordered, the factory-installed jumper should remain in the ICS location.

8 Verify that the return output pad socket (JXP THERM), located between the hybrid output

and the SRE-*-*, has a 0 dB pad (or JXP-ZX jumper) or a JXP-TH*C installed.

9 Set the sweep equipment output level to the amplifier’s design input level. Add insertion

point loss.

10 If required, change the return output pad (JXP OUT) and/or return equalizer to achieve, as

close as possible, a match of the reference level as compared to the node.

11 Verify the sweep response of all insertion points if applicable.

12 Verify that the pad and equalizer values are similar to the map design values.

You can verify proper return alignment by injecting a carrier, at the design level, into any

amplifier at random. Proper alignment is achieved if you observe the reference level at the

headend optical receiver output.

Return levels used for alignment are not necessarily operational system levels. These levels

vary from system to system due to differences in equipment, architectures and design

philosophies. For an in-depth analysis and discussion of the return path, refer to Motorola

reference guide Return Path Level Selection, Setup and Alignment Procedure.

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Motorola STARLINE SERIES Instructions d'exploitation Page 34